Chain of command; although we are a friendly community we have a "chain of command" with the admins making rules, enforcing rules and keeping order: users contribute and have fun but need to remember admins are not democratic, neither are they tyrants - Admins should be approachable and not completely insane with power but at the same time users must treat admins with the respect you give any authority or expect punishment. It's much like the real-world, you cannot walk up to an authority figure and force them to do as you say, empty threats and outright stupidity will only serve to alienate you from the community as a whole - This system may not suit everyone but much like any community we need to acknowledge the fact that contributing is a privilege, not a right and like all privileges it can and should be removed if abused.
General rules; we allow users to post links, funny pictures and "fun" items but within reason. Do not provide links to pornographic sites - rule 34 counts, just so you know - and do not upload pictures that are overly offensive. "Fun" items should only be posted into userpages or talkpages - Do not add them to main articles unless you have a good reason to do so.
Gallery size, position and color; it is never necessary to left the colors of the subs as gray since the background is already dark and it is difficult to read what the subtitles/captions. Also, it is better to leave the gallery's position in the middle instead of right and left because it can interrupt in the editing of other users. The letters of the page might get inside of the gallery code and corrupt its codex, breaking the template. But if the gallery is kept on the middle, it will never happen as the letters and the template are separate in a proper space. Same thing with the videos and their position too. It is better to leave them in the middle like the gallery for the same reason. If there is a section saying: Videos and you put the video to the left said, this page will get a bad design - it is not like this is important. And last, if the images within a gallery are too small, it is better to leave on the max size - such as 300px.
20 pictures minimum; gallery subpages are meant to group hundreds of pictures, 20 at the very least. Only create a new gallery if you can fill it with a minimum of 20 images. New gallery pages that do not fit this criteria will be marked for deletion.
Do not add too many pictures; not only this is not a photo-sharing site, most users who visit here do not have super fast connections. 20 pictures is more than enough for any article, there is no need to put hundreds of pictures. Also, keep in mind that pictures are meant to illustrate the article and provide an image of what is described. Voiding the page of pictures and putting a overly long gallery will only make your article hard to read.
Do not add too many videos: Much like the above. 5 videos is a good enough limit.
No fan-art allowed; only add official art on articles - screenshots, concept art, promotional art, etc. This wiki is not DeviantART, and posting fan-art made by others is copyright infringement. Special cases can be taken into consideration - a render of an organization's symbol, or if you just cannot find a decent official picture by any means.
"Type Of"; always use a short and concise description on the Infobox template's "Type Of" section. Using a category name or a trope name is possible, but clogging it with categories is not only redundant but flooding. Category list belongs in the category list.